<!DOCTYPE html>
<html lang="en">
  <head>
    <meta charset="UTF-8" />
    <meta
      http-equiv="X-UA-Compatible"
      content="IE=edge"
    />
    <meta
      name="viewport"
      content="width=device-width, initial-scale=1.0"
    />
    <title>Document</title>
  </head>
  <body>
    <!-- 以id为app的标签包含的内容就是 view层 -->
    <div id="app">{{msg}}</div>
    <!-- 开发环境版本，包含了有帮助的命令行警告 -->
    <script src="https://cdn.jsdelivr.net/npm/vue@2/dist/vue.js"></script>
    <script>
      // view model
      const vm = new Vue({
        el: '#app',
        data: {
          // model
          msg: 'hello vue'
        }
      })
    </script>
  </body>
</html>
